Major Depressive Disorder (MDD) places a staggering global burden on society. Of all mental disorders, MDD accounts for 4.4% of the total disability-adjusted life years (DALYs) lost and accounts for 11.9% of total years lost due to disability (YLD). With current trends, projection for the year 2020 is that depression will be second only to ischemic heart disease as the cause of DALYs lost worldwide.
A standard method of evaluating levels of MDD in patients is the clinical 17-question “Hamilton-D” or “HAMD” assessment that results in a total score of the patient, which is then translated into a clinical assessment by a physician. To determine the overall or total score, individual ratings are first determined for symptom sub-topics (such as mood, guilt, psychomotor retardation, suicidal tendency, etc.); the total score is the aggregate of the ratings for all sub-topics. Although the HAMD assessment is a standard evaluation method, there are well-known concerns about its validity and reliability.